JavaRestClient操作Elasticsearch分页

落日映苍穹つ 2022-12-24 00:41 184阅读 0赞

# 导包 #

导包可以根据 [文档][Link 1] 里导入依赖  
这里就不写依赖了

# 代码 #

*  from：开始位置
 *  size：每页大小

import com.google.gson.Gson;
    import com.leyou.pojo.Item;
    import org.apache.http.HttpHost;
    import org.elasticsearch.action.search.SearchRequest;
    import org.elasticsearch.action.search.SearchResponse;
    import org.elasticsearch.client.RequestOptions;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.elasticsearch.index.query.QueryBuilders;
    import org.elasticsearch.search.SearchHit;
    import org.elasticsearch.search.SearchHits;
    import org.elasticsearch.search.builder.SearchSourceBuilder;
    import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
    import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
    import org.elasticsearch.search.sort.SortOrder;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.context.junit4.SpringRunner;
    
    import java.io.IOException;
    import java.util.Map;
    
    @RunWith(SpringRunner.class)
    @SpringBootTest
    public class EsdemoFindHighlight { 
    
        private RestHighLevelClient client;
    
        private Gson gson = new Gson();
        /** * 先执行 */
        @Before
        public void init (){ 
            // 初始化HighLevel客户端
            client = new RestHighLevelClient(
                    RestClient.builder(
                            HttpHost.create("http://127.0.0.1:9201"),
                            HttpHost.create("http://127.0.0.1:9202"),
                            HttpHost.create("http://127.0.0.1:9203")
                    )
            );
        }
    
        /** * 高亮 */
        @Test
        public void findSource() throws IOException { 
            //创建搜索对象
            SearchRequest searchRequest = new SearchRequest();
            // 构建查询对象
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            //查询条件
            searchSourceBuilder.query(QueryBuilders.termQuery("字段名1", "字段中的内容"));
            //高亮对象
            HighlightBuilder highlightBuilder = new HighlightBuilder();
            //设置高亮参数
            highlightBuilder.field("字段名1"); //参数要和查询条件字段名一样
            highlightBuilder.preTags("<span style='color:red'>");
            highlightBuilder.postTags("</span>");
            searchSourceBuilder.highlighter(highlightBuilder);
    
            searchRequest.source(searchSourceBuilder);
            //搜索
            SearchResponse search = client.search(searchRequest, RequestOptions.DEFAULT);
            //解析
            SearchHits hits = search.getHits();
            SearchHit[] hitsHits = hits.getHits();
            for (SearchHit hit : hits) { 
                //获取数据
                String jsonStr = hit.getSourceAsString();
                //反序列化
                Item item = gson.fromJson(jsonStr, Item.class);
                //获得返回的高亮数据
                Map<String, HighlightField> highlightFields = hit.getHighlightFields();
                //是否为空
                if(highlightFields!=null){ 
                    //参数要和查询的参数一致
                    HighlightField highlightField = highlightFields.get("字段名1");
                    //判断是否为空
                    if(highlightField.fragments()!=null&&highlightField.fragments().length>0){ 
                        String title = highlightField.fragments()[0].toString();
                        //设置参数将高亮的内容,替换原来的内容
                        item.setTitle(title);
                    }
                }
                //打印结果
                System.out.println("结果:"+item);
            }
        }
        /** * 后执行 */
        @After
        public void close(){ 
            try { 
                client.close();
            } catch (IOException e) { 
                e.printStackTrace();
            }
        }
    }

[Link 1]: https://blog.csdn.net/weixin_44257023/article/details/110130718